kernel/arch/h8300/include/asm/processor.h

   1 /*
   2  * include/asm-h8300/processor.h
   3  *
   4  * Copyright (C) 2002 Yoshinori Sato
   5  *
   6  * Based on: linux/asm-m68nommu/processor.h
   7  *
   8  * Copyright (C) 1995 Hamish Macdonald
   9  */
  10
  11 #ifndef __ASM_H8300_PROCESSOR_H
  12 #define __ASM_H8300_PROCESSOR_H
  13
  14 /*
  15  * Default implementation of macro that returns current
  16  * instruction pointer ("program counter").
  17  */
  18 #define current_text_addr() ({ __label__ _l; _l: &&_l; })
  19
  20 #include <linux/compiler.h>
  21 #include <asm/segment.h>
  22 #include <asm/ptrace.h>
  23 #include <asm/current.h>
  24
  25 static inline unsigned long rdusp(void)
  26 {
  27         extern unsigned int     _sw_usp;
  28
  29         return _sw_usp;
  30 }
  31
  32 static inline void wrusp(unsigned long usp)
  33 {
  34         extern unsigned int     _sw_usp;
  35
  36         _sw_usp = usp;
  37 }
  38
  39 /*
  40  * User space process size: 3.75GB. This is hardcoded into a few places,
  41  * so don't change it unless you know what you are doing.
  42  */
  43 #define TASK_SIZE       (0xFFFFFFFFUL)
  44
  45 #ifdef __KERNEL__
  46 #define STACK_TOP       TASK_SIZE
  47 #define STACK_TOP_MAX   STACK_TOP
  48 #endif
  49
  50 /*
  51  * This decides where the kernel will search for a free chunk of vm
  52  * space during mmap's. We won't be using it
  53  */
  54 #define TASK_UNMAPPED_BASE      0
  55
  56 struct thread_struct {
  57         unsigned long  ksp;             /* kernel stack pointer */
  58         unsigned long  usp;             /* user stack pointer */
  59         unsigned long  ccr;             /* saved status register */
  60         unsigned long  esp0;            /* points to SR of stack frame */
  61         struct {
  62                 unsigned short *addr;
  63                 unsigned short inst;
  64         } breakinfo;
  65 };
  66
  67 #define INIT_THREAD  {                                          \
  68         .ksp  = sizeof(init_stack) + (unsigned long)init_stack, \
  69         .usp  = 0,                                              \
  70         .ccr  = PS_S,                                           \
  71         .esp0 = 0,                                              \
  72         .breakinfo = {                                          \
  73                 .addr = (unsigned short *)-1,                   \
  74                 .inst = 0                                       \
  75         }                                                       \
  76 }
  77
  78 /*
  79  * Do necessary setup to start up a newly executed thread.
  80  *
  81  * pass the data segment into user programs if it exists,
  82  * it can't hurt anything as far as I can tell
  83  */
  84 #if defined(CONFIG_CPU_H8300H)
  85 #define start_thread(_regs, _pc, _usp)                          \
  86 do {                                                            \
  87         (_regs)->pc = (_pc);                                    \
  88         (_regs)->ccr = 0x00;       /* clear all flags */        \
  89         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
  90         (_regs)->sp = ((unsigned long)(_usp)) - sizeof(unsigned long) * 3; \
  91 } while (0)
  92 #endif
  93 #if defined(CONFIG_CPU_H8S)
  94 #define start_thread(_regs, _pc, _usp)                          \
  95 do {                                                            \
  96         (_regs)->pc = (_pc);                                    \
  97         (_regs)->ccr = 0x00;       /* clear kernel flag */      \
  98         (_regs)->exr = 0x78;       /* enable all interrupts */  \
  99         (_regs)->er5 = current->mm->start_data; /* GOT base */  \
 100         /* 14 = space for retaddr(4), vector(4), er0(4) and exr(2) on stack */ \
 101         (_regs)->sp = ((unsigned long)(_usp)) - 14;             \
 102 } while (0)
 103 #endif
 104
 105 /* Forward declaration, a strange C thing */
 106 struct task_struct;
 107
 108 /* Free all resources held by a thread. */
 109 static inline void release_thread(struct task_struct *dead_task)
 110 {
 111 }
 112
 113 /*
 114  * Free current thread data structures etc..
 115  */
 116 static inline void exit_thread(void)
 117 {
 118 }
 119
 120 /*
 121  * Return saved PC of a blocked thread.
 122  */
 123 unsigned long thread_saved_pc(struct task_struct *tsk);
 124 unsigned long get_wchan(struct task_struct *p);
 125
 126 #define KSTK_EIP(tsk)   \
 127         ({                       \
 128                 unsigned long eip = 0;        \
 129                 if ((tsk)->thread.esp0 > PAGE_SIZE &&   \
 130                     MAP_NR((tsk)->thread.esp0) < max_mapnr)      \
 131                         eip = ((struct pt_regs *) (tsk)->thread.esp0)->pc; \
 132                 eip; })
 133
 134 #define KSTK_ESP(tsk)   ((tsk) == current ? rdusp() : (tsk)->thread.usp)
 135
 136 #define cpu_relax()    barrier()
 137 #define cpu_relax_lowlatency()  cpu_relax()
 138
 139 #define HARD_RESET_NOW() ({             \
 140         local_irq_disable();            \
 141         asm("jmp @@0");                 \
 142 })
 143
 144 #endif